You might be deficient in magnesium as meds of every sort [according to Dr. Carolyn Dean MD, ND in her book The Magnesium Miracle] not only block the body's ability to utilize magnesium, but deplete it as the liver detoxes the meds. Insomnia is a symptoms of low magnesium so you might try taking a highly absorbable form such as magnesium chloride, citate, malate or other chelated forms. DON'T take magnesium oxide as it's so poorly absorbed that all it does it give you raging diarrhea. You need to take calcium and vitamins D3 and K with the magnesium as the 4 nutrients work together.

Meds destroyed my ability to sleep, and the two things that have restored it are the cortisol lowering supplement Seriphos and high doses of magnesium. Without those, I don't sleep a wink.